Lifting-jack



(No Model.)

v A. WHITE.

LIPTING JACK.- No. 297,893. I Patented Apr. 29, 1884.

WITNESSES UNITED STATES PATENT OFFICE.

ADDISON WVHITE, OF LYNNVILLE, IOWA.

LlFTING-JACK.

SPECIFICATION forming part of Letters Patent No. 297,893, dated April 29, 1884.

Application filed February 26, 1884. (No model.)

Z'oall whom it may concern- Be it known that I, ADDISON WHITE, a citizen of the United States, residing at Lynnville, in the county of Jasper and State of Iowa, have invented certain new and useful Improvements in Lifting-Jacks; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawing, and to letters or figures of reference marked thereon, which forms a part of this specification.

The figure of the drawing is a representation of a perspective view of my device.

This invention has relation to an improvement in lifting-jacks; and it consists in the construction and novel arrangement of devices, as hereinafter fully described, and pointed out in the appended claims.

In the accompanying drawing, the letter A represents the lever of the jack, which is designed to work against the side of the standard D. The lever is securely connected to the cross-bar fulcrum 0 at one end of the stirrup B. This metallic stirrup is of rectangular form, and consists of two lateral arm-plates, o, and two round cross-bars or pivot-bars connecting said arm-plates at their ends, as shown at c and c. The distance between the arms 22 is equal to the thickness of the support or standard D and of the lever A taken together, and the arms are parallel to each other, so that the lever can be moved freely in the stirrup and the stirrup moved freely on the standard. The cross-bar c at the other end of this stirrup is placed within and is capa- O of the support D, and may be held at any point desired in the notches n, which are formed in the forward wall of the slot.

The stirrup is preferably made of cast-iron, and is capable of sustaining any stress to which it may be subjected in ordinary use. The

portion of the support including the slot and.

notches is likewise usually made of cast-iron. When a weight is raised on the short arm of bl'e of being moved up and down in the slot the lever, and the lever is inany position in which it is desired to remain while the power acting on the long arm is removed and while the weight is still acting on the short arm, the wedge E is driven in between the lever and the upper cross-bar of the stirrup.

The operation firmly sets the lever so that it is held in position by the friction of the wedge.

ADDISON WHITE.

Witnesses:

H. G. EDWARDS, R. L. ARNOLD. 

